The present invention relates to improvements in plastic bags, and more particularly to an apparatus and method and resultant structure wherein a continuous chain of lightweight plastic bags are mounted and held in registry.
More and more operations are being computerized and in the manufacture of thin, lightweight plastic bags, it becomes desirable to controllably handle different product lines. Such handling becomes advantageous and even necessary in maintaining control over the bags for storage, dispensing packing and the like, and one particular special application occurs where the bags have a printable panel on the surface of the bags and the present invention in conjunction with computer print-out equipment makes it possible that a printable panel on the bags can be automatically typed by a computer printer. It is desirable to make a continuous chain of plastic bags and have these chains constructed so that the bags remain in registry and are capable of being received, folded, stored, handled and fed through a computer printer with printing being in registry with a panel on the front of the bag.
One form of bag of this type is formed of polyethylene or similar thin plastic with reclosable fastener strips at the top. The bags are manufactured in sequence and have side seals and end seals and may be formed in a continuous attached chain to be folded or rolled and stored in boxes when the aforesaid printing is not essential. However, when a computer printer is desired, the present invention forms the bags in a continuous chain for storage but in such a manner so that the stored chain can be received by a computer printer with the location of the bags being positive so that printing can occur within the limits of a relatively small panel on the bags. Maintaining the bags in controlled registry is useful for other purposes such as where an indicator mark is carried on the bag to be read by an electric eye or magnetic reader or other automatic reading equipment.
In the manufacture of reclosable bags, normally these are closed at the top by reclosable rib and groove elements while the bottoms are closed either by a fold if before filling or if after filling by a bar or continuous band sealing which heat seals the base of the bag. Another step occurring in the manufacture is the provision of spot seals at the ends of the reclosable rib and groove profiles which reduces the ends within the sealing parameters of the thinner film forming the ends of the bag and maintains the rib and groove profiles in alignment for closing.
It is an object of the present invention to provide an improved continuous bag structure wherein a series of bags are maintained for storage and handling in aligned registry and have the capability of being fed through an electric reader or through a computer printer to print information in a printing panel on one face.
A still further object of the invention is to provide an improved method of making a series of bags which are compatible with computer print-out equipment so that the bag can automatically be typed by a printer with the required information and removed from the chain.
A still further object of the invention is to provide an improved apparatus for the manufacture of bags so that they are attached in registry to the surface of a continuous web of registry insuring support backing such a computer paper and are constructed so that after being printed by a computer printer, they may be individually removed.